If the rifle is primarily a coyote callin' rig, I'd not put a scope on that won't go below 6X, that is just too much for those close moving targets. If it's primarily a prairie dog plinkin' rig, than a 6x18 would work quite well.
I do like my 4.5 x 14 x 40, BUT when the action gets close and fast, even the 4.5 is almost too much.